Metered dose inhalers of various configurations are known for dispensing medication into the mouth of a patient. The medication is expelled from an actuator and inhaled by the patient, whereupon, the medication is absorbed in the mouth, throat and lungs. A medicine canister is inserted into the actuator so that the actuator may direct the flow of medication out a mouthpiece. The medicine canister is a small pressurized container with a nozzle. By pressing the nozzle, the contents of the canister are dispensed.
Some actuators have integral electronics which monitor various factors related to the dispensing of medication. The timing of the inhalation with respect to the dispensing of medication is important to assure delivery of the medication. The number of times medication is dispensed is also important to monitor. If the actuator is changed, however, the electronics integral to the actuator cannot be reused.
Actuators are standard components provided by many different manufacturers which have a variety of geometric configurations. For example, medicine canisters of different sizes require unique actuators. Further, some medicine manufacturers use proprietary actuators of unique configurations. Additionally, other factors dictate different configurations of actuators such that there is no standard actuator which can dispense all medications.
Applying a non-dedicated electronics module to a variety of actuators of different configurations is described in U.S. Pat. No. 5,809,997, which is assigned to the same assignee as the present application. With the electronics module adaptable to different actuators, this module can be reused, when a different actuator is utilized. In accordance with this previous design, to measure the timing of inhalation and use the non-dedicated electronics module, the actuator needs to be modified. A hole must be formed in the body of the actuator body to allow insertion of an air flow sensor in the path of the patient's inspiration and/or expiration. It would be advantageous to provide a combination of an electronics module and actuator hardware that further facilitates their use and interchangeability.